t’s pretty much guaranteed that naming your movie after a lewd sex act is going to attract far more attention than if you went with something a little more traditional, but the fact that director Olly Blackburn actually works said act into the story makes “Donkey Punch” less reprehensible than it sounds. Unfortunately, it still isn’t very good. Fans of movies like “Hostel” and “Turistas” will find plenty to love about this amateur peepshow turned horror film, but those looking for the next great genre flick will only discover a stale British thriller that plays out exactly like every other movie before it.

Three best friends – Tammi (Nichola Burley), Kim (Jaime Winstone) and Lisa (Sian Breckin) – are vacationing in Spain when a few guys (Tom Burke, Julian Morris and Jay Taylor) promising a good time invite them back to their yacht. Once aboard, the girls are introduced to the fourth member of the group, Sean (Robert Boulter), and set off for sea where they start drinking a little champagne, taking some drugs, and videotaping each other having sex. When one of the guys gets the brilliant idea to donkey punch one of the girls (a knock to the back of the neck that allegedly increases a man's orgasm) and accidentally kills her, the others argue whether they should try to cover it up by dumping the body. As tempers flare, betrayal sets in, igniting a series of retaliations among the survivors.

What follows is pretty suspenseful stuff, as the second act focuses on developing each character while they weigh their legal and moral responsibility for the death of the girl. One would assume that the guy who did the donkey punching would be the only person in trouble, but since there was drug use, non-consensual sex and trespassing involved, everyone is somewhat liable. The constant change in possession of the videotape documenting the act only increases the tension, but by the time the movie becomes a funhouse of murder (complete with stupid decisions and surprisingly bloodless deaths), it loses its edge and reverts back to the kind of trashy, second-rate horror film that the first act hinted at eventually becoming.

Co-writers Olly Blackburn and David Bloom deserve some credit for masterminding a darkly comical, death-by-flare homage to "Dead Calm," but the others aren’t nearly as inspired, and one is even ruined by some amateurish editing meant to hide the film’s low budget. Thankfully, Blackburn has enlisted a talented cast of young up-and-comers that elevate the quality of the material – though it’s a little disappointing to see them give so much for so little in return. Is it too much to ask for a character who doesn’t become a complete idiot the minute people start dying? Apparently so, because while “Donkey Punch” should have been as shocking and controversial as its title suggests, it’s just as dull as the characters that inhabit it.